annelids and molluscs

Question 1

what are the main characteristics of annilids

Answer 1

segmented bristleworms

Question 2

what is a true coelom

Answer 2

is a cavity inside the mesoderm allowing for segmentation

Question 3

what is a benefit of being segmented worm if i was a worm and you still loved me as a worm

Answer 3

reduces muscle activity needed for movement

Question 4

what are the two classes and what are the subclasses

Answer 4

polychaetae, clitellate, with the sub classes oligochaete(earthworms) and hirudinea(leeches)

Question 5

what is a parapodia and what is its purpose

Answer 5

paired lateral extensions of the body wall, mainly for movement, found in epibenthic polychetae

Question 6

what are the two main types of polychetea

Answer 6

sedimentary and errant`

Question 7

what are some distinguishing features of the two types

Answer 7

errant tend to have jointed chaetae that remain the same along the length of its body whereas sedentary tend to have variance in their chaetae and hook shaped setae

Question 8

what are some characteristics of oligochaete

Answer 8

few and simple chaetae simultaneous hermaphrodites, small numbers of large eggs and cocoons

Question 9

what are some characteristics of hirudinea

Answer 9

no chaetae, suckers at both ends, single hydrostatic unit, eggs in cocoons

Question 10

what are some general features of molluscs

Answer 10

shell, a mantle which produces the shell, a mantle cavity with gills and anus, viscera mass with a foot and head

Question 11

name some classes of mollusca

Answer 11

Bivalvia, cephalopodan, gastropod, aplacophora, polyplacophoran, schaphopoda, monocophra

Question 12

what are some features of aplacophora

Answer 12

worm like body, all marine and no shell but calcareous spicules

Question 13

what are some features of monoplacophora

Answer 13

limpet like appearance, signs of segmentation, primitive molluscs

Question 14

what are some features of polyplacophora or chitons

Answer 14

mostly grazers, found in shallow waters, shell of 8 overlapping plates bound with leathery gills

Question 15

what is some features of scaphopda

Answer 15

tusk shells, open at one end, sedimentary

Question 16

what are some features of bivalves

Answer 16

marine burrowing filter feeder, two shells connected by ligament

Question 17

what are some features of gastropods

Answer 17

spiral shell, although possible modified or absent, many grazers, vectors for many parasites or diseases

Question 18

what are some features of cephalopods

Answer 18

all marine mostly predators, highly evolved, shell absent or reduced and internal

Question 19

what is a mollusc radula

Answer 19

a mouthpart containing chitous teeth scrape food particles off rocks sits in a radula sack

Question 20

what is the mantle cavity

Answer 20

an empty space containing the gills

Question 21

what are some modifications of bivalves

Answer 21

larger mantle cavity, no head buccal mass or radula, highly modified for filter feeding